Hoist.



K. IWAHORI.

HOIST.

APPLICATION FILED MAY20,1909.

952,742. Patented Mar.22,1910.

2 SHEETS-SHEET 1.

ANDREW a. GRAHAM co, wum'o-LnnocmPnEfis, WASHINGTON. 11c

K. IWAHORI.

HOIST.

APPLICATION FILED MAY 20,1909.

Patented Mar. 22, 1910.

Z SHEETS-SHEET 2.

E jzywrfimwm Witnesses ANDRkW a. GRAHAM c0 Fnmmumoempums WAS NVNGIUNFD.a

' tudinal section of the same.

KIGI-IIZO IWAI-IORI, OF WORCESTER, MASSACHUSETTS.

I-IOIST.

Specification of Letters Patent.

Patented Mar. 22, 1910.

Application filed. May 20, 1909. Serial No. 497,324.

T 0 all whom "it may concern:

Be it known that I, KIoHIzo IWAHORI, a citizen of Japan, residing atWorcester, in the county of Worcester and State of Massachusetts, haveinvented certain new and useful Improvements in Hoists, of which thefollowing is a specification, reference being had therein to theaccompanying drawing.

This invention relates to pulley blocks and has for its object theproduction of novel means for automatically locking the gears andpreventing the same from rotating in one direction.

Another object of this invention is the production of a pulley block,which is simple in construction, efficient in operation and consists ofa comparatively small number of arts.

With these and other objects in view this invention consists of certainnovel constructions, combinations, and arrangements of parts as will behereinafter fully described and claimed.

In the drawings: Figure 1 is a side elevation of the block, showing theblock with the pawl in a locked position. Fig. 2 is a side elevation ofthe same, showing the pawl in an unlocked position. Fig. 3 is a longi-Fig. 4. is a detail perspective of the locking pawl. Fig. 5 is a detailperspective of the gear for controlling the locking pawl. Fig. 6 is adetail perspective view of the clamping dog.

Referring to the drawings by numerals, 1 designates a casing upon whichis ournaled shafts 2 and 3, and upon the shafts 2 and 3, and inside ofthe casing 1, are positioned pulleys 4: and 5. Mounted upon the outerend of the shaft 2 is a pawl-controlling gear 6, which is fixedlysecured to the shaft 2 by means of a locking-pin 7 which pin fits in alongitudinally-extending slot 8, formed in the gear wheel andregistering with a slot formed upon the shaft 2, therefore, holding thegear 6 against independent rotary movement upon the shaft. It will,therefore, be obvious that the rotation of the gear 6 will be controlledby the rotation of the pulley 4 and vice versa. The gear 6 is providedupon the outer edge thereof with a flangeportion 9, which extends aroundthe periphery of said gear wheel, and has extending to one side thereofteeth portions 10, constituting the gear. The outer edge of the teethportions 10 are in the same plane with the outer edge of the flange 9. Adog or pawl 11 is pivotally mounted upon the casing 1 by means of a boltor screw 12, which passes thropgh the outer-enlarged end 13 of the Thepawl 11 is provided, at its lower end, with a tooth-engaging portion, orinwardlyextending portion, 1 which is adapted to engage teeth upon anintermediate gear 15 hereinafter described. Intermediate the ends of thedog 13 is formed a tapering inwardlyextending portion 16, which isslightly curved upon its lower face 17 and is straight upon its upperface 18, so as to bind against the teeth 10 upon the gear wheel 6. Asthe gear wheel 6 is rotated and the extension 16 engages the wheelbetween two of the teeth, and as the gear wheel 6 is rotated farther inthe direction of the arrow, shown in Fig. 1, the pawl will be raised outof engagement with the gear wheel 15 for the reason that the edge of theteeth 10 will engage the slightly curved end of said inwardly-extendingtapering portion 16 and thereby push the pawl 11 out of engagement withthe teeth of both the gears 6 and 15. However, as soon as the gear isrotated, so as to allow the pawl or dog to readily engage the teeth orgears, which is caused by its own weight, the same will engage the teethof both of the gears and prevent either of the pulleys L or 5 fromrotating. When.

the gear 6 tends to rotate left-handedly, or so to speak,counter-clockwise the teeth 10 will bind against the upper surfaces 18of the inwardly-extending portion 16 and the teeth upon the gear 15 willbind against the lower end of the inwardly-extending portion 14, andthereby firmly hold the pawl in engagement therewith.

It will be obvious that by having the gear 6 provided with a flangearound the outer edge thereof, and the inwardly-extending portionabutting against said flange, that the pawl 11 will be held againstlateral movement and remove most of the strain from the pivot 12. Thefunction of the flange 9 can readily be seen from Fig. 1, as theinwardly-extending portion 16 is positioned between two of the teeth,the flange 6will engage the side of the inwardly-exby said casing, apivoted pawl carried by tending portion, and, therefore, it will beobvious that the pawl will be held against any lateral movement.

Secured to the shaft 3, in a similar manner as the gear 6, is a gear 19,which meshes with the intermediate gear 15, hereinbefore mentioned, andthe gears are so arranged as to mesh with each other and cause onepulley to rotate when the other is rotated. It will, therefore, beobvious that by having a locking means constructed, as hereinbeforedescribed, that for this reason both pulleys will be firmly locked andheld against rotation in one direction.

A dog 20 is pivotally secured within the casing l by means of a pivotpin 21 and collars 22 are positioned upon each side of the dog 20 andhold said dog out of contact with the sides of the casing. The dog 20 isprovided with an angularly-disposed portion or upwardly-extendingportion 23, which is provided upon its inner face with a roughened orcorrugated portion 24. The dog 20 is provided intermediate its ends witha transverselyextending aperture 25 through which is adapted to pass arope 26, which passes over the pulleys 1 and 5. The dog 20 is providedupon its under surface with a groove 27, so as to prevent the ropepassing around the pulley 5 from being engaged by the dog and therebycausing the same to wear when the dog is in the position shown in dottedlines in Fig. 1. When the lifting force is released upon the end 28 ofthe rope 26, the rope will tend to slide over the pulley in the oppositedirection in which the pulleys had been previously revolving, and asthis happens the dog will be swung from the position shown in dottedlines to the position shown in full lines and the roughened orcorrugated face 2% will engage the rope and firmly hold the same inengagement with the pulley, and prevent it from sliding thereover.

What I claim is:

1. In a device of the class described the combination with a casing, ofa plurality of shafts extending therethrough, pulleys carried by eachshaft, gear wheels carried by each shaft and adapted to be rotated whensaid pulley is rotated, a gear wheel interposed between thefirst-mentioned gear wheels, and means carried by said casing andadapted to engage said intermediate gear and one of said first-mentionedgears for preventing the rotation of said pulleys in one direction.

2. In a device of the class described the combination with a casing,shafts passing through said casing and having pulley wheels securedthereto, gear wheels carried said casing and adapted to engage one of Isaid gears at one end, and means formed l intermediate the ends of saidpawl and adapted to engage another of said gear wheels for holding bothof said wheels against rotation in one direction.

3. In a device of the class described the combination with a casing,gears carried by said casing, of a pivoted pawl provided with an angleextension, formed upon one end thereof, said angle extension adapted toengage teeth upon one of said gears, said pawl provided with aninwardlyextending tapers ing portion adapted to engage teeth upon one ofthe other gears, whereby when said last-mentioned gear is rotated in onedirection the angle extension upon the lower end of said pawl will bewithdrawn from said first-mentioned gear and allow the same to berotated in one direction, and when said last-mentioned gear is rotatedin the oppo site direction said pulley will engage teeth on both of saidgears and hold said gears against rotation in the opposite direction.

4. In a device of the class described the combination with a casing, apawl-controL ling gear, a lower gear, and an intermediate gear meshingwith said pawl-controlling gear and said lower gear, of a pivoted pawlcarried by said casing, said clog-controlling gear provided on theperiphery thereof with a flat portion terminating in laterally-extendinggear teeth, said pawl provided with teeth-engaging portions intermediateits ends and adapted to engage said teeth, and said flange adapted toprevent lateral movement of said pawl upon said casing when inengagement with said flange.

5. In a device of the class described, the

combination with a casing, pulleys carried thereby, gear wheels carriedby said casing and cooperating with said pulleys, means adapted toengage said gear wheels for holding the same against rotation in onedirection, a dog pivotally mounted within said casing between saidpulleys, and provided with an angularly disposed portion, said angularportion corrugated upon the inner surface thereof, said dog providedwith a transversely extending aperture intermediate its ends, beingadapted to receive a cable adapted to pass over the pulleys, and saiddog adapted to grip the cable when the same is released and bind thecable upon one of said pulleys for preventing the sliding of the cablefrom the pulleys.

6. In a device of the class described, the combination with a casing,pulleys carried thereby, a dog pivotally mounted upon said casingintermediate said pulleys, said dog provided with an angularly disposedportion, and provided with an aperture extending transverselytherethrough near the junc tion of said angularly disposed portion andthe body portion of the dog, and said aperture adapted to receive acable adapted to pass over said pulleys, said dog provided upon itsunder surface with a groove adapted to prevent the dog from engaging thecable adapted to pass around one of said pulleys and said dog adapted tobe thrown into an operative position when the cable is released.

In testimony whereof I hereunto aifix my signature in presence of twowitnesses.

KIGHIZO IWAHORI.

WVitnesses:

HOWARD E. GRANDELL, WILLIAM A. VAN DEVENTER.

